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  <p class="align-right"><strong>built-in predicate</strong></p>
<section id="logtalk-load-2">
<span id="predicates-logtalk-load-2"></span><span id="index-0"></span><h1><code class="docutils literal notranslate"><span class="pre">logtalk_load/2</span></code><a class="headerlink" href="#logtalk-load-2" title="Link to this heading"></a></h1>
<section id="description">
<h2>Description<a class="headerlink" href="#description" title="Link to this heading"></a></h2>
<div class="highlight-logtalk notranslate"><div class="highlight"><pre><span></span><span class="k">logtalk_load</span>(<span class="nv">File</span>, <span class="nv">Flags</span>)
<span class="k">logtalk_load</span>(<span class="nv">Files</span>, <span class="nv">Flags</span>)
</pre></div>
</div>
<p>Compiles to disk and then loads to memory a <a class="reference internal" href="../../glossary.html#term-source-file"><span class="xref std std-term">source file</span></a> or a list
of source files using a list of compiler flags. The Logtalk source file name
extension (by default, <code class="docutils literal notranslate"><span class="pre">.lgt</span></code>) can be omitted. Source file paths can be
absolute, relative to the current directory, or use <a class="reference internal" href="../../glossary.html#term-library-notation"><span class="xref std std-term">library notation</span></a>.
Compiler flags are represented as <em>flag(value)</em>. This predicate can also be
used to compile Prolog source files as Logtalk source code. When no recognized
Logtalk or Prolog extension is specified, the compiler tries first to append a
Logtalk source file extension and then a Prolog source file extension. If that
fails, the compiler tries to use the file name as-is. For a description of the
available compiler flags, please see the <a class="reference internal" href="../../userman/programming.html#programming-flags"><span class="std std-ref">Compiler flags</span></a> section in
the User Manual. The recognized Logtalk and Prolog file extensions are defined
in the <a class="reference internal" href="../../glossary.html#term-adapter-file"><span class="xref std std-term">backend adapter files</span></a>. The recognized Logtalk
and Prolog file extensions are defined in the
<a class="reference internal" href="../../glossary.html#term-adapter-file"><span class="xref std std-term">backend adapter files</span></a>.</p>
<p>When this predicate is called from the top-level interpreter, relative source
file paths are resolved using the current working directory. When the calls
are made from a source file, relative source file paths are resolved by
default using the source file directory (unless a
<a class="reference internal" href="../../userman/programming.html#flag-relative-to"><span class="std std-ref">relative_to</span></a> flag is passed).</p>
<p>Note that only the errors related to problems in the predicate argument
are listed below. This predicate fails on the first error found during
compilation of a source file. In this case, the source file contents is
not loaded.</p>
<div class="admonition warning">
<p class="admonition-title">Warning</p>
<p>The compiler flags specified in the second argument only apply to the
files listed in the first argument and not to any files that those files
may load or compile. Notably, if you are loading a <a class="reference internal" href="../../glossary.html#term-loader-file"><span class="xref std std-term">loader file</span></a>,
the flags only apply to the loader file itself and not to the files
loaded by it.</p>
</div>
</section>
<section id="modes-and-number-of-proofs">
<h2>Modes and number of proofs<a class="headerlink" href="#modes-and-number-of-proofs" title="Link to this heading"></a></h2>
<div class="highlight-logtalk notranslate"><div class="highlight"><pre><span></span><span class="k">logtalk_load</span>(<span class="o">@</span>source_file_name, <span class="o">@</span>list(compiler_flag)) <span class="o">-</span> zero_or_one
<span class="k">logtalk_load</span>(<span class="o">@</span>list(source_file_name), <span class="o">@</span>list(compiler_flag)) <span class="o">-</span> zero_or_one
</pre></div>
</div>
</section>
<section id="errors">
<h2>Errors<a class="headerlink" href="#errors" title="Link to this heading"></a></h2>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">File</span></code> is a variable:</div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">instantiation_error</span></code></div>
</div>
<div class="line"><code class="docutils literal notranslate"><span class="pre">Files</span></code> is a variable or a list with an element which is a variable:</div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">instantiation_error</span></code></div>
</div>
<div class="line"><code class="docutils literal notranslate"><span class="pre">File</span></code>, or an element <code class="docutils literal notranslate"><span class="pre">File</span></code> of the <code class="docutils literal notranslate"><span class="pre">Files</span></code> list, is neither a variable nor a source file name:</div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">type_error(source_file_name,</span> <span class="pre">File)</span></code></div>
</div>
<div class="line"><code class="docutils literal notranslate"><span class="pre">File</span></code>, or an element <code class="docutils literal notranslate"><span class="pre">File</span></code> of the <code class="docutils literal notranslate"><span class="pre">Files</span></code> list, uses library notation but the library does not exist:</div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">existence_error(library,</span> <span class="pre">Library)</span></code></div>
</div>
<div class="line"><code class="docutils literal notranslate"><span class="pre">File</span></code> or an element <code class="docutils literal notranslate"><span class="pre">File</span></code> of the <code class="docutils literal notranslate"><span class="pre">Files</span></code> list, does not exist:</div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">existence_error(file,</span> <span class="pre">File)</span></code></div>
</div>
<div class="line"><code class="docutils literal notranslate"><span class="pre">Flags</span></code> is a variable or a list with an element which is a variable:</div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">instantiation_error</span></code></div>
</div>
<div class="line"><code class="docutils literal notranslate"><span class="pre">Flags</span></code> is neither a variable nor a proper list:</div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">type_error(list,</span> <span class="pre">Flags)</span></code></div>
</div>
<div class="line">An element <code class="docutils literal notranslate"><span class="pre">Flag</span></code> of the <code class="docutils literal notranslate"><span class="pre">Flags</span></code> list is not a valid compiler flag:</div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">type_error(compiler_flag,</span> <span class="pre">Flag)</span></code></div>
</div>
<div class="line">An element <code class="docutils literal notranslate"><span class="pre">Flag</span></code> of the <code class="docutils literal notranslate"><span class="pre">Flags</span></code> list defines a value for a read-only compiler flag:</div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">permission_error(modify,</span> <span class="pre">flag,</span> <span class="pre">Flag)</span></code></div>
</div>
<div class="line">An element <code class="docutils literal notranslate"><span class="pre">Flag</span></code> of the <code class="docutils literal notranslate"><span class="pre">Flags</span></code> list defines an invalid value for a flag:</div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">domain_error(flag_value,</span> <span class="pre">Flag+Value)</span></code></div>
</div>
</div>
</section>
<section id="examples">
<h2>Examples<a class="headerlink" href="#examples" title="Link to this heading"></a></h2>
<div class="highlight-logtalk notranslate"><div class="highlight"><pre><span></span><span class="c">% compile and load the &quot;list&quot; source file in the</span>
<span class="c">% current directory using default compiler flags:</span>
| <span class="o">?-</span> <span class="k">logtalk_load</span>(list, []).

<span class="c">% compile and load the &quot;tree&quot; source file in the &quot;types&quot;</span>
<span class="c">% library directory with the source_data flag turned on:</span>
| <span class="o">?-</span> <span class="k">logtalk_load</span>(types(tree)).

<span class="c">% compile and load the &quot;file_system&quot; source file in the</span>
<span class="c">% current directory with portability warnings suppressed:</span>
| <span class="o">?-</span> <span class="k">logtalk_load</span>(file_system, [portability(silent)]).
</pre></div>
</div>
<div class="admonition seealso">
<p class="admonition-title">See also</p>
<p><a class="reference internal" href="logtalk_compile_1.html#predicates-logtalk-compile-1"><span class="std std-ref">logtalk_compile/1</span></a>,
<a class="reference internal" href="logtalk_compile_2.html#predicates-logtalk-compile-2"><span class="std std-ref">logtalk_compile/2</span></a>,
<a class="reference internal" href="logtalk_load_1.html#predicates-logtalk-load-1"><span class="std std-ref">logtalk_load/1</span></a>,
<a class="reference internal" href="logtalk_make_0.html#predicates-logtalk-make-0"><span class="std std-ref">logtalk_make/0</span></a>,
<a class="reference internal" href="logtalk_make_1.html#predicates-logtalk-make-1"><span class="std std-ref">logtalk_make/1</span></a>,
<a class="reference internal" href="logtalk_library_path_2.html#predicates-logtalk-library-path-2"><span class="std std-ref">logtalk_library_path/2</span></a></p>
</div>
</section>
</section>


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